Winkler, a fourth-term Democratic state representative from Golden Valley, who had been considering running for Secretary of State said in an interview that he had decided to call off that bid. He said he made that decision before the storm brewed about his Twitter comment.

After a heated email exchange with conservative activists Jack Tomczak and John Gilmore on Twitter, Winkler apolgized for the use of the slur against Supreme Court Justice Clarence Thomas. In another tweet, he said: "I did not understand "Uncle Tom" as a racist term, and there seems to be some debate about it. I do apologize for it, however."

"I didn't think it was offensive to suggest that Justice Thomas should be even more concerned about racial discrimination than colleagues." Winkler tweeted at another point. "But if such a suggestion is offensive, I apologize."

He said in an interview that he realized in the reaction to his initial tweet that the term "Uncle Tom" is offensive to a lot of people.

"I intended to point out the fact that Justice Thomas had turned his back on African-American civil rights. I did not intend it as a racially derogatory term and I probably reacted too hastily in using a word that is very loaded," Winkler said. He said that he thought of the term as simply one that meant turncoat. "I guess my judgment is way off."

Asked if he believes his use of the term on Twitter will hurt his political career in the future, he said: "I don't know. I hope people judge people on the merits of what they do in public office and not on the firestorm of a term that is used hastily but with no malintent."

The incident drew outrage on social media, national attention and blunt words from a Democratic colleague.

"I thought it was unfortunate. I talked to Ryan today and told him as much. I thought it was a poor choice of words and frankly as leaders and public officials, we have to be very careful about what we say," said Deputy Senate Majoirty Leader Jeff Hayden, DFL-Minneapolis.

Hayden, who is African-American, said that Winkler should have been aware of the impact of his choice of words and suggested that he might want to do some research into African-American history.

"It most certainly comes off as prejudiced and biased and insensitive," Hayden said, who said he still considers Winkler a friend and a good lawmaker.